Re: [PATCH 6/6] drm/i915: Convert the register access tracepoint to be conditional

[Ben Widawsky <ben@bwidawsk.net>]

On Fri, Jul 12, 2013 at 06:08:27PM +0100, Chris Wilson wrote:
> The TRACE_EVENT_CONDITION is supposed to generate more efficient code
> than if (cond) trace(), which is what we are currently using inside the
> register access functions.
> 
> v2: Rebase onto uncore
> 
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

One thing I've thought about this is a trace_on_once, or trace_on_poll
would be cool for polled reads. Obviously we can post-process it, but we
always risk losing events if we fill up too much of the ringbuffer with
stuff we don't care about.

In any case, I very much like the condition added to the trace itself,
and reading probably the same docs as you agree it should be faster.

Looking over our code. It looks like I missed trace events when writing
the PTEs in i915_gem_gtt.c. Can you get around to fixing those up?

[snip]

-- 
Ben Widawsky, Intel Open Source Technology Center